This invention relates to an improved volume pump having a plurality of pump chambers.
The rotary pump heretofore used contains a flexible impeller and operates at a high delivery rate with a sufficient self-suction as well as lifting properties despite its compact structure, nevertheless requires a high motive power and produces undesired noise during the operation, for which reason the conventional rotary pump is unsuited for hospital or house hold use. Further, in the conventional rotary pump, the impeller is usually worked under the severe environments and likely subjected to abrasion and damage within a relatively short time, so that the necessity arises of frequently replacing the impeller by a fresh one with resulting inconvenience, poor economy and increased cost. Moreover, the material of which the impeller may be made is restricted and the impeller material being selected to be resistive to chemicals and heat may not have sufficient mechanical strength.
To improve the foregoing disadvantages and difficulties, the inventors have invented after extensive researches an improved volume pump in which the outer edges of the vanes are shrouded with a sleeve to form a plurality of the compartments in the pump chamber which at its center is provided with a deflection means and closed at its opposite open sides by side plates and also provided with a suction and delivery means where the deflection means is actuated to compress each compartment of the pump chamber successively thereby to achieve the pumping action with a variation of volume of each compartment.